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    <ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="../intern.html">Inter Modules</a></li><li><a href="index.html">bytecode</a></li><li><a href="index.html#3">Chapter 3: Their Instructions</a></li><li><b>Inter Value Pairs</b></li></ul></div>
<p class="purpose">Two consecutive bytecode words are used to store a single value in binary Inter.</p>

<ul class="toc"><li><a href="3-ivp.html#SP2">&#167;2. Pairs</a></li><li><a href="3-ivp.html#SP4">&#167;4. Numeric pairs</a></li><li><a href="3-ivp.html#SP6">&#167;6. Textual pairs</a></li><li><a href="3-ivp.html#SP8">&#167;8. Real pairs</a></li><li><a href="3-ivp.html#SP11">&#167;11. Dictionary word pairs</a></li><li><a href="3-ivp.html#SP13">&#167;13. Symbolic pairs</a></li><li><a href="3-ivp.html#SP15">&#167;15. Glob pairs</a></li><li><a href="3-ivp.html#SP17">&#167;17. The undef pair</a></li><li><a href="3-ivp.html#SP19">&#167;19. Pairs in bytecode</a></li><li><a href="3-ivp.html#SP21">&#167;21. Transposition</a></li><li><a href="3-ivp.html#SP22">&#167;22. Verification</a></li></ul><hr class="tocbar">

<p class="commentary firstcommentary"><a id="SP1" class="paragraph-anchor"></a><b>&#167;1. </b>About time to define the types we're using to represent Inter words in C.
It turns out to be more convenient to define these by what amounts to <span class="extract"><span class="extract-syntax">#define</span></span>
than to use <span class="extract"><span class="extract-syntax">typedef</span></span>.
</p>

<pre class="definitions code-font"><span class="definition-keyword">define</span> <span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span>
<span class="definition-keyword">define</span> <span class="constant-syntax">signed_inter_ti</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span>
</pre>
<p class="commentary firstcommentary"><a id="SP2" class="paragraph-anchor"></a><b>&#167;2. Pairs.</b>A constant value in Inter code is represented by a pair of <span class="extract"><span class="extract-syntax">inter_ti</span></span> values:
the format and the content.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">typedef</span><span class="plain-syntax"> </span><span class="reserved-syntax">struct</span><span class="plain-syntax"> </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> {</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">data_format</span><span class="plain-syntax">; </span><span class="comment-syntax"> one of the </span><span class="extract"><span class="extract-syntax">*_IVAL</span></span><span class="comment-syntax"> values below</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">data_content</span><span class="plain-syntax">;</span>
<span class="plain-syntax">} </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax">;</span>
</pre>
<ul class="endnotetexts"><li>The structure inter_pair is private to this section.</li></ul>
<p class="commentary firstcommentary"><a id="SP3" class="paragraph-anchor"></a><b>&#167;3. </b>These are the formats. Note that changing any of these values would invalidate
existing Inter binary files, necessitating a bump of <a href="1-tiv.html" class="internal">The Inter Version</a>.
</p>

<pre class="definitions code-font"><span class="definition-keyword">enum</span> <span class="constant-syntax">DECIMAL_IVAL</span><span class="plain-syntax"> </span><span class="identifier-syntax">from</span><span class="plain-syntax"> </span><span class="constant-syntax">0x10000</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">HEX_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">BINARY_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">SIGNED_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">TEXTUAL_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">REAL_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">DWORD_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">PDWORD_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">SYMBOLIC_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">GLOB_IVAL</span>
<span class="definition-keyword">enum</span> <span class="constant-syntax">UNDEF_IVAL</span>
</pre>
<p class="commentary firstcommentary"><a id="SP4" class="paragraph-anchor"></a><b>&#167;4. Numeric pairs.</b>These can represent any <span class="extract"><span class="extract-syntax">inter_ti</span></span> value, and are used when the data is a
literal integer. Note that they express both an integer and also a preferred
way to print it out &mdash; as decimal, hexadecimal, binary, or signed decimal.
But these are all numerically equal. They affect only the way in which the
Inter program is printed to text files, not the meaning of the program.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::number</span><button class="popup" onclick="togglePopup('usagePopup1')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup1">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::number</span></span>:<br/>The Constant Construct - <a href="4-tcc2.html#SP11">&#167;11</a><br/>The Instance Construct - <a href="4-tic2.html#SP3">&#167;3</a></span></button><span class="plain-syntax">(</span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">N</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">DECIMAL_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">N</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::number_in_base</span><button class="popup" onclick="togglePopup('usagePopup2')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup2">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::number_in_base</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_2">&#167;12.2</a></span></button><span class="plain-syntax">(</span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">N</span><span class="plain-syntax">, </span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">b</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">switch</span><span class="plain-syntax"> (</span><span class="identifier-syntax">b</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="constant-syntax">2</span><span class="plain-syntax">: </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">BINARY_IVAL</span><span class="plain-syntax">; </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="constant-syntax">10</span><span class="plain-syntax">: </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">DECIMAL_IVAL</span><span class="plain-syntax">; </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="constant-syntax">16</span><span class="plain-syntax">: </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">HEX_IVAL</span><span class="plain-syntax">; </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="identifier-syntax">default:</span><span class="plain-syntax"> </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"only bases 2, 10, 16 are supported"</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    }</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">N</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::signed_number</span><button class="popup" onclick="togglePopup('usagePopup3')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup3">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::signed_number</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_2">&#167;12.2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">N</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">SIGNED_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = (</span><span class="constant-syntax">inter_ti</span><span class="plain-syntax">) </span><span class="identifier-syntax">N</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::number_from_I6_notation</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">S</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> *</span><span class="identifier-syntax">overflow_flag</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">overflow_flag</span><span class="plain-syntax">) *</span><span class="identifier-syntax">overflow_flag</span><span class="plain-syntax"> = </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">sign</span><span class="plain-syntax"> = </span><span class="constant-syntax">1</span><span class="plain-syntax">, </span><span class="identifier-syntax">from</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">unsigned</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">base</span><span class="plain-syntax"> = </span><span class="constant-syntax">10</span><span class="plain-syntax">; </span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">overflow_point</span><span class="plain-syntax"> = </span><span class="constant-syntax">0x7fffffff</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Str::prefix_eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">S</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"-"</span><span class="plain-syntax">, </span><span class="constant-syntax">1</span><span class="plain-syntax">)) { </span><span class="identifier-syntax">sign</span><span class="plain-syntax"> = -1; </span><span class="identifier-syntax">from</span><span class="plain-syntax"> = </span><span class="constant-syntax">1</span><span class="plain-syntax">; </span><span class="identifier-syntax">overflow_point</span><span class="plain-syntax"> = </span><span class="constant-syntax">0x80000000</span><span class="plain-syntax">; }</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Str::prefix_eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">S</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"$"</span><span class="plain-syntax">, </span><span class="constant-syntax">1</span><span class="plain-syntax">)) { </span><span class="identifier-syntax">base</span><span class="plain-syntax"> = </span><span class="constant-syntax">16</span><span class="plain-syntax">; </span><span class="identifier-syntax">from</span><span class="plain-syntax"> = </span><span class="constant-syntax">1</span><span class="plain-syntax">; </span><span class="identifier-syntax">overflow_point</span><span class="plain-syntax"> = </span><span class="constant-syntax">0x100000000</span><span class="plain-syntax">; }</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Str::prefix_eq</span><span class="plain-syntax">(</span><span class="identifier-syntax">S</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"$$"</span><span class="plain-syntax">, </span><span class="constant-syntax">2</span><span class="plain-syntax">)) { </span><span class="identifier-syntax">base</span><span class="plain-syntax"> = </span><span class="constant-syntax">2</span><span class="plain-syntax">; </span><span class="identifier-syntax">from</span><span class="plain-syntax"> = </span><span class="constant-syntax">2</span><span class="plain-syntax">; </span><span class="identifier-syntax">overflow_point</span><span class="plain-syntax"> = </span><span class="constant-syntax">0x100000000</span><span class="plain-syntax">; }</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">N</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pos</span><span class="plain-syntax">.</span><span class="element-syntax">index</span><span class="plain-syntax"> &lt; </span><span class="identifier-syntax">from</span><span class="plain-syntax">) </span><span class="reserved-syntax">continue</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="identifier-syntax">inchar32_t</span><span class="plain-syntax"> </span><span class="identifier-syntax">c</span><span class="plain-syntax"> = </span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">), </span><span class="identifier-syntax">d</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">c</span><span class="plain-syntax"> &gt;= </span><span class="character-syntax">'a'</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">c</span><span class="plain-syntax"> &lt;= </span><span class="character-syntax">'z'</span><span class="plain-syntax">)) </span><span class="identifier-syntax">d</span><span class="plain-syntax"> = </span><span class="identifier-syntax">c</span><span class="plain-syntax">-</span><span class="character-syntax">'a'</span><span class="plain-syntax">+10;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">c</span><span class="plain-syntax"> &gt;= </span><span class="character-syntax">'A'</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">c</span><span class="plain-syntax"> &lt;= </span><span class="character-syntax">'Z'</span><span class="plain-syntax">)) </span><span class="identifier-syntax">d</span><span class="plain-syntax"> = </span><span class="identifier-syntax">c</span><span class="plain-syntax">-</span><span class="character-syntax">'A'</span><span class="plain-syntax">+10;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">c</span><span class="plain-syntax"> &gt;= </span><span class="character-syntax">'0'</span><span class="plain-syntax">) &amp;&amp; (</span><span class="identifier-syntax">c</span><span class="plain-syntax"> &lt;= </span><span class="character-syntax">'9'</span><span class="plain-syntax">)) </span><span class="identifier-syntax">d</span><span class="plain-syntax"> = </span><span class="identifier-syntax">c</span><span class="plain-syntax">-</span><span class="character-syntax">'0'</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">else</span><span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-ivp.html#SP17" class="function-link"><span class="function-syntax">InterValuePairs::undef</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">d</span><span class="plain-syntax"> &gt;= </span><span class="identifier-syntax">base</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-ivp.html#SP17" class="function-link"><span class="function-syntax">InterValuePairs::undef</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax">        </span><span class="identifier-syntax">N</span><span class="plain-syntax"> = </span><span class="identifier-syntax">base</span><span class="plain-syntax">*</span><span class="identifier-syntax">N</span><span class="plain-syntax"> + (</span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax">) </span><span class="identifier-syntax">d</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">N</span><span class="plain-syntax"> &gt;= </span><span class="identifier-syntax">overflow_point</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">pos</span><span class="plain-syntax">.</span><span class="element-syntax">index</span><span class="plain-syntax"> &gt; </span><span class="constant-syntax">34</span><span class="plain-syntax">)) {</span>
<span class="plain-syntax">            </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">overflow_flag</span><span class="plain-syntax">) *</span><span class="identifier-syntax">overflow_flag</span><span class="plain-syntax"> = </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">            </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-ivp.html#SP17" class="function-link"><span class="function-syntax">InterValuePairs::undef</span></a><span class="plain-syntax">();</span>
<span class="plain-syntax">        }</span>
<span class="plain-syntax">    }</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-ivp.html#SP4" class="function-link"><span class="function-syntax">InterValuePairs::number</span></a><span class="plain-syntax">((</span><span class="constant-syntax">inter_ti</span><span class="plain-syntax">) (</span><span class="identifier-syntax">sign</span><span class="plain-syntax">*</span><span class="identifier-syntax">N</span><span class="plain-syntax">));</span>
<span class="plain-syntax">}</span>

<span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::to_number</span><button class="popup" onclick="togglePopup('usagePopup4')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup4">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_number</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_1">&#167;12.1</a><br/>Metadata - <a href="3-mtd.html#SP4_1">&#167;4.1</a><br/>The Constant Construct - <a href="4-tcc2.html#SP10">&#167;10</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP5" class="function-link"><span class="function-syntax">InterValuePairs::is_number</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::to_base</span><button class="popup" onclick="togglePopup('usagePopup5')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup5">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_base</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_1">&#167;12.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">switch</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">DECIMAL_IVAL:</span><span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">10</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">SIGNED_IVAL:</span><span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">10</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">HEX_IVAL:</span><span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">16</span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">BINARY_IVAL:</span><span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">2</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    }</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP5" class="paragraph-anchor"></a><b>&#167;5. </b>Testing:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_number</span><button class="popup" onclick="togglePopup('usagePopup6')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup6">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_number</span></span>:<br/><a href="3-ivp.html#SP4">&#167;4</a>, <a href="3-ivp.html#SP22">&#167;22</a><br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a><br/>Metadata - <a href="3-mtd.html#SP4_1">&#167;4.1</a><br/>The Constant Construct - <a href="4-tcc2.html#SP10">&#167;10</a>, <a href="4-tcc2.html#SP11">&#167;11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">DECIMAL_IVAL</span><span class="plain-syntax">) ||</span>
<span class="plain-syntax">        (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">HEX_IVAL</span><span class="plain-syntax">) ||</span>
<span class="plain-syntax">        (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">BINARY_IVAL</span><span class="plain-syntax">) ||</span>
<span class="plain-syntax">        (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">SIGNED_IVAL</span><span class="plain-syntax">))</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_one</span><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><a href="3-ivp.html#SP5" class="function-link"><span class="function-syntax">InterValuePairs::is_number</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">)) &amp;&amp;</span>
<span class="plain-syntax">        (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> == </span><span class="constant-syntax">1</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_zero</span><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><a href="3-ivp.html#SP5" class="function-link"><span class="function-syntax">InterValuePairs::is_number</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">)) &amp;&amp;</span>
<span class="plain-syntax">        (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> == </span><span class="constant-syntax">0</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP6" class="paragraph-anchor"></a><b>&#167;6. Textual pairs.</b>These can represent an arbitrarily long literal string of text.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::from_text</span><button class="popup" onclick="togglePopup('usagePopup7')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup7">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::from_text</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_4">&#167;12.4</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_bookmark</span><span class="plain-syntax"> *</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">, </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP7" class="function-link"><span class="function-syntax">InterBookmark::tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP6" class="function-link"><span class="function-syntax">InterBookmark::package</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">ID</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::create_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">ID</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">Str::copy</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax">, </span><span class="identifier-syntax">text</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">TEXTUAL_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ID</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_text</span><button class="popup" onclick="togglePopup('usagePopup8')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup8">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_text</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_3">&#167;12.3</a><br/>Metadata - <a href="3-mtd.html#SP6_1">&#167;6.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP7" class="function-link"><span class="function-syntax">InterValuePairs::is_text</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">))</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP7" class="paragraph-anchor"></a><b>&#167;7. </b>Testing:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_text</span><button class="popup" onclick="togglePopup('usagePopup9')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup9">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_text</span></span>:<br/><a href="3-ivp.html#SP6">&#167;6</a><br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a><br/>Metadata - <a href="3-mtd.html#SP6_1">&#167;6.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">TEXTUAL_IVAL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP8" class="paragraph-anchor"></a><b>&#167;8. Real pairs.</b>These represent real numbers, but they do so by storing them as literal strings
prefaced by a sign character, <span class="extract"><span class="extract-syntax">+</span></span> or <span class="extract"><span class="extract-syntax">-</span></span>.
</p>

<p class="commentary">Though the argument here has type <span class="extract"><span class="extract-syntax">double</span></span>, we are not guaranteeing that level
of service, and in fact these are likely to be no better than <span class="extract"><span class="extract-syntax">float</span></span> precision
on some platforms.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::real</span><span class="plain-syntax">(</span><span class="reserved-syntax">inter_bookmark</span><span class="plain-syntax"> *</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">, </span><span class="reserved-syntax">double</span><span class="plain-syntax"> </span><span class="identifier-syntax">g</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP7" class="function-link"><span class="function-syntax">InterBookmark::tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP6" class="function-link"><span class="function-syntax">InterBookmark::package</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">ID</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::create_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">ID</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">g</span><span class="plain-syntax"> &gt; </span><span class="constant-syntax">0</span><span class="plain-syntax">) </span><span class="identifier-syntax">WRITE_TO</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax">, </span><span class="string-syntax">"+"</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">WRITE_TO</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax">, </span><span class="string-syntax">"%g"</span><span class="plain-syntax">, </span><span class="identifier-syntax">g</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">REAL_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ID</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP9" class="paragraph-anchor"></a><b>&#167;9. </b>Inform 6 notation begins with a dollar <span class="extract"><span class="extract-syntax">$</span></span> &mdash; for example, <span class="extract"><span class="extract-syntax">$+3.1415</span></span> &mdash; but
otherwise is similar.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::real_from_I6_notation</span><button class="popup" onclick="togglePopup('usagePopup10')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup10">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::real_from_I6_notation</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_6">&#167;12.6</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_bookmark</span><span class="plain-syntax"> *</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">, </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP7" class="function-link"><span class="function-syntax">InterBookmark::tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP6" class="function-link"><span class="function-syntax">InterBookmark::package</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">ID</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::create_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">ID</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">LOOP_THROUGH_TEXT</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">)</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">) != </span><span class="character-syntax">'$'</span><span class="plain-syntax">)</span>
<span class="plain-syntax">            </span><span class="identifier-syntax">PUT_TO</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax">, </span><span class="identifier-syntax">Str::get</span><span class="plain-syntax">(</span><span class="identifier-syntax">pos</span><span class="plain-syntax">));</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">REAL_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ID</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_textual_real</span><button class="popup" onclick="togglePopup('usagePopup11')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup11">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_textual_real</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_5">&#167;12.5</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP10" class="function-link"><span class="function-syntax">InterValuePairs::is_real</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">))</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP10" class="paragraph-anchor"></a><b>&#167;10. </b>Testing:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_real</span><button class="popup" onclick="togglePopup('usagePopup12')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup12">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_real</span></span>:<br/><a href="3-ivp.html#SP9">&#167;9</a><br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">REAL_IVAL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP11" class="paragraph-anchor"></a><b>&#167;11. Dictionary word pairs.</b>These are relevant only to command-parser IF projects, and none of these values
otherwise ever exist. They exist in two forms, one marked as possibly plural,
the other not so marked. Just because a word is marked plural, it doesn't follow
that every usage of it will be in a plural noun context: so "singular" here is
best read as "no comment on the number of this if it is used in a noun context".
</p>

<p class="commentary">It would be appealing to remove these from the design of Inter, but that's harder
than it seems. Dictionary words have semantics which are hard to imitate with
other values which would be legal in a constant context.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::from_singular_dword</span><button class="popup" onclick="togglePopup('usagePopup13')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup13">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::from_singular_dword</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_8">&#167;12.8</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_bookmark</span><span class="plain-syntax"> *</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">, </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">word</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP7" class="function-link"><span class="function-syntax">InterBookmark::tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP6" class="function-link"><span class="function-syntax">InterBookmark::package</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">ID</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::create_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">ID</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">Str::copy</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax">, </span><span class="identifier-syntax">word</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">DWORD_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ID</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::from_plural_dword</span><button class="popup" onclick="togglePopup('usagePopup14')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup14">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::from_plural_dword</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_10">&#167;12.10</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_bookmark</span><span class="plain-syntax"> *</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">, </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">word</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP7" class="function-link"><span class="function-syntax">InterBookmark::tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP6" class="function-link"><span class="function-syntax">InterBookmark::package</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">ID</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::create_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">ID</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">Str::copy</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax">, </span><span class="identifier-syntax">word</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">PDWORD_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ID</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_dictionary_word</span><button class="popup" onclick="togglePopup('usagePopup15')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup15">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_dictionary_word</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_7">&#167;12.7</a>, <a href="3-iitf.html#SP12_9">&#167;12.9</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP12" class="function-link"><span class="function-syntax">InterValuePairs::is_dword</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">))</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP12" class="paragraph-anchor"></a><b>&#167;12. </b>Testing:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_dword</span><button class="popup" onclick="togglePopup('usagePopup16')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup16">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_dword</span></span>:<br/><a href="3-ivp.html#SP11">&#167;11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">DWORD_IVAL</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">PDWORD_IVAL</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_singular_dword</span><button class="popup" onclick="togglePopup('usagePopup17')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup17">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_singular_dword</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">DWORD_IVAL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_plural_dword</span><button class="popup" onclick="togglePopup('usagePopup18')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup18">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_plural_dword</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">PDWORD_IVAL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP13" class="paragraph-anchor"></a><b>&#167;13. Symbolic pairs.</b>All other pairs represent known literal values, but a symbolic pair delegates
that by saying "it's the value of this symbol". For example, a symbolic pair
could mean "whatever the value of <span class="extract"><span class="extract-syntax">WORDSIZE</span></span> is". Note that this symbol might
not even be defined in the current Inter tree: it could be wired to a plug, which
expects to find a definition in some other tree when linking takes place.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::symbolic</span><button class="popup" onclick="togglePopup('usagePopup19')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup19">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::symbolic</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_14">&#167;12.14</a>, <a href="3-iitf.html#SP12_14_1">&#167;12.14.1</a><br/>The Val Construct - <a href="5-tvc.html#SP4">&#167;4</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_bookmark</span><span class="plain-syntax"> *</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-ivp.html#SP13" class="function-link"><span class="function-syntax">InterValuePairs::symbolic_in</span></a><span class="plain-syntax">(</span><a href="2-bkm.html#SP6" class="function-link"><span class="function-syntax">InterBookmark::package</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">), </span><span class="identifier-syntax">S</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::symbolic_in</span><span class="plain-syntax">(</span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">S</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax"> = </span><a href="2-pck.html#SP4" class="function-link"><span class="function-syntax">InterPackage::tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">S</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">internal_error</span><span class="plain-syntax">(</span><span class="string-syntax">"no symbol"</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">SYMBOLIC_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><a href="2-st.html#SP16" class="function-link"><span class="function-syntax">InterSymbolsTable::id_from_symbol</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">, </span><span class="identifier-syntax">pack</span><span class="plain-syntax">, </span><span class="identifier-syntax">S</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_symbol</span><button class="popup" onclick="togglePopup('usagePopup20')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup20">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_symbol</span></span>:<br/>The Constant Construct - <a href="4-tcc2.html#SP10">&#167;10</a>, <a href="4-tcc2.html#SP11">&#167;11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_symbols_table</span><span class="plain-syntax"> *</span><span class="identifier-syntax">T</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP14" class="function-link"><span class="function-syntax">InterValuePairs::is_symbolic</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">))</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-st.html#SP13" class="function-link"><span class="function-syntax">InterSymbolsTable::symbol_from_ID</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">T</span><span class="plain-syntax">, </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_symbol_not_following</span><button class="popup" onclick="togglePopup('usagePopup21')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup21">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_symbol_not_following</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_13">&#167;12.13</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_symbols_table</span><span class="plain-syntax"> *</span><span class="identifier-syntax">T</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP14" class="function-link"><span class="function-syntax">InterValuePairs::is_symbolic</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">))</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-st.html#SP13" class="function-link"><span class="function-syntax">InterSymbolsTable::symbol_from_ID_not_following</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">T</span><span class="plain-syntax">, </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_symbol_in</span><button class="popup" onclick="togglePopup('usagePopup22')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup22">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_symbol_in</span></span>:<br/>Metadata - <a href="3-mtd.html#SP5_1">&#167;5.1</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-ivp.html#SP13" class="function-link"><span class="function-syntax">InterValuePairs::to_symbol</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><a href="2-pck.html#SP10" class="function-link"><span class="function-syntax">InterPackage::scope</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pack</span><span class="plain-syntax">));</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_symbol_at</span><button class="popup" onclick="togglePopup('usagePopup23')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup23">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_symbol_at</span></span>:<br/>The Constant Construct - <a href="4-tcc2.html#SP9">&#167;9</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">P</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-ivp.html#SP13" class="function-link"><span class="function-syntax">InterValuePairs::to_symbol</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><a href="2-pck.html#SP12" class="function-link"><span class="function-syntax">InterPackage::scope_of</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">));</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP14" class="paragraph-anchor"></a><b>&#167;14. </b>Testing:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_symbolic</span><button class="popup" onclick="togglePopup('usagePopup24')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup24">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_symbolic</span></span>:<br/><a href="3-ivp.html#SP13">&#167;13</a><br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a><br/>Metadata - <a href="3-mtd.html#SP5_1">&#167;5.1</a><br/>The Constant Construct - <a href="4-tcc2.html#SP9">&#167;9</a>, <a href="4-tcc2.html#SP10">&#167;10</a>, <a href="4-tcc2.html#SP11">&#167;11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">SYMBOLIC_IVAL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP15" class="paragraph-anchor"></a><b>&#167;15. Glob pairs.</b>Globs are a desperation measure. They represent a value, but which is expressed
in terms of raw source code which will produce that value. For instance, if you
knew your Inter code would be compiled to C, you could have a glob of <span class="extract"><span class="extract-syntax">"time(0)"</span></span>,
but of course this wouldn't work in compiled in a constant context, and wouldn't
work if the Inter were aimed at any other final code-generator than C.
</p>

<p class="commentary">Globs were needed in the development stages of Inter but are now never produced
anywhere in the Inter tool chain except in response to the textual Inter notation
below. They cling on here just in case they are needed again.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::glob</span><button class="popup" onclick="togglePopup('usagePopup25')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup25">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::glob</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_12">&#167;12.12</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_bookmark</span><span class="plain-syntax"> *</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">, </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP7" class="function-link"><span class="function-syntax">InterBookmark::tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax"> = </span><a href="2-bkm.html#SP6" class="function-link"><span class="function-syntax">InterBookmark::package</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">IBM</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">ID</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::create_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax"> = </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">ID</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">Str::copy</span><span class="plain-syntax">(</span><span class="identifier-syntax">text_storage</span><span class="plain-syntax">, </span><span class="identifier-syntax">text</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">GLOB_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ID</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="identifier-syntax">text_stream</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::to_glob_text</span><button class="popup" onclick="togglePopup('usagePopup26')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup26">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_glob_text</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12_11">&#167;12.11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP16" class="function-link"><span class="function-syntax">InterValuePairs::is_glob</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">))</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-tw.html#SP7" class="function-link"><span class="function-syntax">InterWarehouse::get_text</span></a><span class="plain-syntax">(</span><a href="2-it.html#SP3" class="function-link"><span class="function-syntax">InterTree::warehouse</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">), </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP16" class="paragraph-anchor"></a><b>&#167;16. </b>Testing:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_glob</span><button class="popup" onclick="togglePopup('usagePopup27')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup27">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_glob</span></span>:<br/><a href="3-ivp.html#SP15">&#167;15</a><br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">GLOB_IVAL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP17" class="paragraph-anchor"></a><b>&#167;17. The undef pair.</b>There is just one <span class="extract"><span class="extract-syntax">undef</span></span> pair. It means "undefined value", and allows functions
which return <a href="3-ivp.html#SP2" class="internal">inter_pair</a> to signal that they couldn't work anything useful out.
(See for example <a href="3-ivp.html#SP4" class="internal">InterValuePairs::number_from_I6_notation</a> above.)
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::undef</span><button class="popup" onclick="togglePopup('usagePopup28')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup28">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::undef</span></span>:<br/><a href="3-ivp.html#SP4">&#167;4</a><br/>Inter in Text Files - <a href="3-iitf.html#SP12_16">&#167;12.16</a><br/>The Constant Construct - <a href="4-tcc2.html#SP6_2_1">&#167;6.2.1</a>, <a href="4-tcc2.html#SP6_3">&#167;6.3</a>, <a href="4-tcc2.html#SP8">&#167;8</a><br/>The Instance Construct - <a href="4-tic2.html#SP4">&#167;4</a>, <a href="4-tic2.html#SP6">&#167;6</a><br/>The PropertyValue Construct - <a href="4-tpc7.html#SP4">&#167;4</a>, <a href="4-tpc7.html#SP6">&#167;6</a><br/>The Variable Construct - <a href="4-tvc.html#SP4">&#167;4</a>, <a href="4-tvc.html#SP6">&#167;6</a><br/>The Ref Construct - <a href="5-trc.html#SP4">&#167;4</a>, <a href="5-trc.html#SP6">&#167;6</a><br/>The Val Construct - <a href="5-tvc.html#SP4">&#167;4</a>, <a href="5-tvc.html#SP6">&#167;6</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">void</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="constant-syntax">UNDEF_IVAL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP18" class="paragraph-anchor"></a><b>&#167;18. </b>Testing:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::is_undef</span><button class="popup" onclick="togglePopup('usagePopup29')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup29">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::is_undef</span></span>:<br/>Inter in Text Files - <a href="3-iitf.html#SP12">&#167;12</a><br/>The Instance Construct - <a href="4-tic2.html#SP3">&#167;3</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> == </span><span class="constant-syntax">UNDEF_IVAL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP19" class="paragraph-anchor"></a><b>&#167;19. Pairs in bytecode.</b>In binary Inter, value pairs are always stored as consecutive fields in the
bytecode of instructions. These fields should be read or written only with the
following functions:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::get</span><button class="popup" onclick="togglePopup('usagePopup30')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup30">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::get</span></span>:<br/>Verifying Inter - <a href="3-vi.html#SP11">&#167;11</a><br/>The Constant Construct - <a href="4-tcc2.html#SP4">&#167;4</a>, <a href="4-tcc2.html#SP7">&#167;7</a>, <a href="4-tcc2.html#SP8">&#167;8</a>, <a href="4-tcc2.html#SP9">&#167;9</a>, <a href="4-tcc2.html#SP10">&#167;10</a>, <a href="4-tcc2.html#SP11">&#167;11</a><br/>The Instance Construct - <a href="4-tic2.html#SP2">&#167;2</a>, <a href="4-tic2.html#SP3">&#167;3</a>, <a href="4-tic2.html#SP5">&#167;5</a>, <a href="4-tic2.html#SP6">&#167;6</a><br/>The PropertyValue Construct - <a href="4-tpc7.html#SP2">&#167;2</a>, <a href="4-tpc7.html#SP6">&#167;6</a><br/>The Variable Construct - <a href="4-tvc.html#SP2">&#167;2</a>, <a href="4-tvc.html#SP6">&#167;6</a><br/>The Ref Construct - <a href="5-trc.html#SP6">&#167;6</a><br/>The Val Construct - <a href="5-tvc.html#SP2">&#167;2</a>, <a href="5-tvc.html#SP6">&#167;6</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">field</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax"> = </span><span class="identifier-syntax">P</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">W</span><span class="plain-syntax">.</span><span class="element-syntax">instruction</span><span class="plain-syntax">[</span><span class="identifier-syntax">field</span><span class="plain-syntax">];</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">P</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">W</span><span class="plain-syntax">.</span><span class="element-syntax">instruction</span><span class="plain-syntax">[</span><span class="identifier-syntax">field</span><span class="plain-syntax">+1];</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>

<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::set</span><button class="popup" onclick="togglePopup('usagePopup31')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup31">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::set</span></span>:<br/>The Constant Construct - <a href="4-tcc2.html#SP4">&#167;4</a>, <a href="4-tcc2.html#SP8">&#167;8</a><br/>The Instance Construct - <a href="4-tic2.html#SP2">&#167;2</a>, <a href="4-tic2.html#SP3">&#167;3</a><br/>The PropertyValue Construct - <a href="4-tpc7.html#SP2">&#167;2</a><br/>The Variable Construct - <a href="4-tvc.html#SP2">&#167;2</a><br/>The Val Construct - <a href="5-tvc.html#SP2">&#167;2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">field</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">P</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">W</span><span class="plain-syntax">.</span><span class="element-syntax">instruction</span><span class="plain-syntax">[</span><span class="identifier-syntax">field</span><span class="plain-syntax">] = </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="identifier-syntax">P</span><span class="plain-syntax">-&gt;</span><span class="element-syntax">W</span><span class="plain-syntax">.</span><span class="element-syntax">instruction</span><span class="plain-syntax">[</span><span class="identifier-syntax">field</span><span class="plain-syntax">+1] = </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP20" class="paragraph-anchor"></a><b>&#167;20. </b>When creating new instructions, <a href="3-ivp.html#SP19" class="internal">InterValuePairs::set</a> cannot be used
because the two words of a pair need to be supplied as two <span class="extract"><span class="extract-syntax">inter_ti</span></span> values.
For that purpose only, the following functions may be used:
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::to_word1</span><button class="popup" onclick="togglePopup('usagePopup32')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup32">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_word1</span></span>:<br/>The Constant Construct - <a href="4-tcc2.html#SP2">&#167;2</a><br/>The Instance Construct - <a href="4-tic2.html#SP2">&#167;2</a><br/>The PropertyValue Construct - <a href="4-tpc7.html#SP2">&#167;2</a><br/>The Variable Construct - <a href="4-tvc.html#SP2">&#167;2</a><br/>The Ref Construct - <a href="5-trc.html#SP2">&#167;2</a><br/>The Val Construct - <a href="5-tvc.html#SP2">&#167;2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
<span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::to_word2</span><button class="popup" onclick="togglePopup('usagePopup33')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup33">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::to_word2</span></span>:<br/>The Constant Construct - <a href="4-tcc2.html#SP2">&#167;2</a><br/>The Instance Construct - <a href="4-tic2.html#SP2">&#167;2</a><br/>The PropertyValue Construct - <a href="4-tpc7.html#SP2">&#167;2</a><br/>The Variable Construct - <a href="4-tvc.html#SP2">&#167;2</a><br/>The Ref Construct - <a href="5-trc.html#SP2">&#167;2</a><br/>The Val Construct - <a href="5-tvc.html#SP2">&#167;2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP21" class="paragraph-anchor"></a><b>&#167;21. Transposition.</b>See <a href="3-iibf.html" class="internal">Inter in Binary Files</a> for more on this. Basically the idea is that those
pairs holding text or package resource ID numbers will need correction when read
in from a binary Inter file (because in that process, resource ID numbers change).
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="function-syntax">InterValuePairs::transpose</span><button class="popup" onclick="togglePopup('usagePopup34')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup34">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::transpose</span></span>:<br/>The Constant Construct - <a href="4-tcc2.html#SP4">&#167;4</a><br/>The Instance Construct - <a href="4-tic2.html#SP2">&#167;2</a><br/>The PropertyValue Construct - <a href="4-tpc7.html#SP2">&#167;2</a><br/>The Variable Construct - <a href="4-tvc.html#SP2">&#167;2</a><br/>The Val Construct - <a href="5-tvc.html#SP2">&#167;2</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> *</span><span class="identifier-syntax">grid</span><span class="plain-syntax">, </span><span class="constant-syntax">inter_ti</span><span class="plain-syntax"> </span><span class="identifier-syntax">grid_extent</span><span class="plain-syntax">,</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_error_message</span><span class="plain-syntax"> **</span><span class="identifier-syntax">E</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">switch</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">DWORD_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">PDWORD_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">TEXTUAL_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">REAL_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">GLOB_IVAL:</span>
<span class="plain-syntax">            </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax"> = </span><span class="identifier-syntax">grid</span><span class="plain-syntax">[</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">];</span>
<span class="plain-syntax">            </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    }</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">;</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP22" class="paragraph-anchor"></a><b>&#167;22. Verification.</b>Some minimal sanity checks on a pair, which can be performed quickly. There are
numerous ways bad data could still pass this, but it will certainly catch random
garbage, and doesn't take much time.
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="reserved-syntax">inter_error_message</span><span class="plain-syntax"> *</span><span class="function-syntax">InterValuePairs::verify</span><button class="popup" onclick="togglePopup('usagePopup35')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup35">Usage of <span class="code-font"><span class="function-syntax">InterValuePairs::verify</span></span>:<br/>Verifying Inter - <a href="3-vi.html#SP11">&#167;11</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">owner</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">P</span><span class="plain-syntax">,</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">pair</span><span class="plain-syntax">, </span><span class="reserved-syntax">inter_type</span><span class="plain-syntax"> </span><span class="identifier-syntax">type</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_symbols_table</span><span class="plain-syntax"> *</span><span class="identifier-syntax">scope</span><span class="plain-syntax"> = </span><a href="2-pck.html#SP10" class="function-link"><span class="function-syntax">InterPackage::scope</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">owner</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">scope</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="identifier-syntax">scope</span><span class="plain-syntax"> = </span><a href="2-in.html#SP6" class="function-link"><span class="function-syntax">Inode::globals</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-ivp.html#SP5" class="function-link"><span class="function-syntax">InterValuePairs::is_number</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">pair</span><span class="plain-syntax">)) </span><span class="named-paragraph-container code-font"><a href="3-ivp.html#SP22_1" class="named-paragraph-link"><span class="named-paragraph">Check this is in range for the type</span><span class="named-paragraph-number">22.1</span></a></span>
<span class="plain-syntax">    </span><span class="reserved-syntax">switch</span><span class="plain-syntax"> (</span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_format</span><span class="plain-syntax">) {</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">SYMBOLIC_IVAL:</span><span class="plain-syntax"> </span><span class="named-paragraph-container code-font"><a href="3-ivp.html#SP22_2" class="named-paragraph-link"><span class="named-paragraph">Check this is reasonable, if we know what it is yet</span><span class="named-paragraph-number">22.2</span></a></span><span class="plain-syntax">;</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">DWORD_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">PDWORD_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">TEXTUAL_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">REAL_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">GLOB_IVAL:</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">case</span><span class="plain-syntax"> </span><span class="identifier-syntax">UNDEF_IVAL:</span>
<span class="plain-syntax">            </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    }</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-in.html#SP15" class="function-link"><span class="function-syntax">Inode::error</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"value of unknown category"</span><span class="plain-syntax">, </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">);</span>
<span class="plain-syntax">}</span>
</pre>
<p class="commentary firstcommentary"><a id="SP22_1" class="paragraph-anchor"></a><b>&#167;22.1. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Check this is in range for the type</span><span class="named-paragraph-number">22.1</span></span><span class="comment-syntax"> =</span>
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax">    </span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">long</span><span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">I</span><span class="plain-syntax"> = (</span><span class="constant-syntax">signed_inter_ti</span><span class="plain-syntax">) </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-idt.html#SP22" class="function-link"><span class="function-syntax">InterTypes::literal_is_in_range</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="plain-syntax">, </span><span class="identifier-syntax">type</span><span class="plain-syntax">) == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">)</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-in.html#SP15" class="function-link"><span class="function-syntax">Inode::error</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"value out of range"</span><span class="plain-syntax">, </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="3-ivp.html#SP22">&#167;22</a>.</li></ul>
<p class="commentary firstcommentary"><a id="SP22_2" class="paragraph-anchor"></a><b>&#167;22.2. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">Check this is reasonable, if we know what it is yet</span><span class="named-paragraph-number">22.2</span></span><span class="comment-syntax"> =</span>
</p>

<pre class="displayed-code all-displayed-code code-font">
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">symb</span><span class="plain-syntax"> = </span><a href="2-st.html#SP13" class="function-link"><span class="function-syntax">InterSymbolsTable::symbol_from_ID</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">scope</span><span class="plain-syntax">, </span><span class="identifier-syntax">pair</span><span class="plain-syntax">.</span><span class="element-syntax">data_content</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">symb</span><span class="plain-syntax"> == </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-in.html#SP15" class="function-link"><span class="function-syntax">Inode::error</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"no such symbol"</span><span class="plain-syntax">, </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="2-sym.html#SP9" class="function-link"><span class="function-syntax">InterSymbol::misc_but_undefined</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">symb</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="2-sym.html#SP18" class="function-link"><span class="function-syntax">InterSymbol::defined_elsewhere</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">symb</span><span class="plain-syntax">)) </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">;</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><a href="3-idt.html#SP24" class="function-link"><span class="function-syntax">InterTypes::expresses_value</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">symb</span><span class="plain-syntax">) == </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">)</span>
<span class="plain-syntax">        </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="2-in.html#SP15" class="function-link"><span class="function-syntax">Inode::error</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="identifier-syntax">I</span><span class="string-syntax">"nonconstant symbol"</span><span class="plain-syntax">, </span><a href="2-sym.html#SP19" class="function-link"><span class="function-syntax">InterSymbol::identifier</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">symb</span><span class="plain-syntax">));</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">inter_type</span><span class="plain-syntax"> </span><span class="identifier-syntax">symbol_type</span><span class="plain-syntax"> = </span><a href="3-idt.html#SP24" class="function-link"><span class="function-syntax">InterTypes::of_symbol</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">symb</span><span class="plain-syntax">);</span>
<span class="plain-syntax">    </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><a href="3-idt.html#SP23" class="function-link"><span class="function-syntax">InterTypes::can_be_used_as</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">symbol_type</span><span class="plain-syntax">, </span><span class="identifier-syntax">type</span><span class="plain-syntax">,</span>
<span class="plain-syntax">        </span><a href="2-sym.html#SP19" class="function-link"><span class="function-syntax">InterSymbol::identifier</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">symb</span><span class="plain-syntax">), </span><a href="2-in.html#SP9" class="function-link"><span class="function-syntax">Inode::get_error_location</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">));</span>
</pre>
<ul class="endnotetexts"><li>This code is used in <a href="3-ivp.html#SP22">&#167;22</a>.</li></ul>
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